You need to buy the good kit! I can tell by your numbers that these are pool store numbers and may or may not be reliable. There is no way to get a reading of 15 on CYA or 97, 93, or 268. Those tests are simply not that precise. In addition, unless you have a total green slime pit, there is no way that your chlorine numbers can be right. FC + CC = TC always. So, for your readings to be right, then your CC would have to be 8ppm which I highly doubt. I'd also be a little wary of a pool store that wouldn't recognize that those chlorine numbers were wrong ----- unless it might have just been a typo on your part.

Have you backwashed your filter any? If so, did you note your clean filter pressure afterwards and is the pressure rising to indicate that the filter is actually filtering particles out?